Foreign Minister Penny Wong is continuing Australia's diplomatic pushback against China in the Pacific.
Ms Wong will visit leaders in Samoa and Tonga over the next few days, offering social and economic support in order to strengthen ties.
Her visit comes after both nations signed deals with China.
Ms Wong was sworn in on May 24 and is making her second trip to the Pacific in nine days. Last week she addressed the Pacific Islands Forum in Fiji.
During that time, China's Foreign Minister Wang Yi has visited five Pacific nations, signed a dozen bilateral agreements but failed to clinch a security and trade deal with 10 countries.
Before leaving Australia last night, Ms Wong pledged to work for better relations with Pacific countries.
"We understand that we need to work together like never before, for our peoples and for generations to come.
"We want to make a uniquely Australian contribution to help build a stronger Pacific family."
Wang last Saturday told Samoan Prime Minister Afioga Fiame Naomi Mataafa that China "does not target the third parties and does not seek exclusive rights" in working with Pacific countries.
"China is willing to enhance communication with all countries that care about Pacific Island Countries, especially Australia and New Zealand, and give full play to respective strengths to carry out more trilateral cooperation on the basis of respecting Pacific Island countries' wishes," he said, according to a Chinese readout of the meeting.
Prime Minister Anthony Albanese will fly to Indonesia on Sunday.
– Reported with Associated Press